This application is a substitute of application Ser. No. 256,892 filed Apr. 23, 1981, now abandoned.
Diamond drill bits have become more practical in recent years because of the commercially available polycrystalline diamond disc which can be attached to a support stud, thereby providing a stud assembly which can be placed within the bottom of a bit body to form a cutting face. As the diamond bit penetrates a formation, only the lowermost crescent shaped edge portion of the layer of diamond material on the disc is subjected to extreme abrasive wear. Consequently, the efficiency of the cutting action of the bit diminishes as the wear progresses, and eventually the bit must be replaced, although perhaps 80% of the polycrystalline layer of diamond material on the disc has been unused.
In my co-pending substitute patent application Ser. No. 803,326 filed Dec. 2, 1985, and Ser. No. 803,331 filed Dec. 2,1985, there is set forth method and apparatus by which a stud assembly can be removed from a bit body, rotated about the longitudinal axial centerline thereof, and replaced into the bit body, thereby taking advantage of the unworn portion of the diamond bit. In the past, in order to carry out this operation, it has been necessary to heat the bit body so that differential expansion between the stud assembly and bit body alleviates the task of extracting the stud assembly from the stud socket.
It would therefore be advantageous to be able to remove a stud assembly from a bit body without incorporating differential expansion between the bit body and stud assembly. It would be desirable to be able to remove the stud assembly from the bit body, reorient the stud assembly in a definite predetermined relative position respective to the bit body, and reassemble the stud assembly into its socket. These desirable goals are the subject of the present invention.